This invention relates to elevator systems which employ electromagnetic signals for communicating between an elevator dispatch controller and fixtures, such as hall fixtures on each floor, so that the fixtures may be used to enter data to make requests for service and for the elevator system to respond to or inform the viewers on the floors. The elevator dispatch controller may be a group controller for a bank of elevators or a single controller for a single elevator.
A conventional elevator system has an installation for each floor which includes an up hall call fixture, such as a request button, for requesting an elevator car from the group controller; and, an associated light for signaling that the group controller has registered the request (except for the highest floor). Similarly, the elevator system includes a down hall call request button with an associated light to indicate that the group controller has registered the request (except for the lowest floor). The elevator system also includes a gong for providing an audible signal that an elevator car is about to arrive.
In addition, on each floor, each elevator hatchway has associated with it a set of hall lantern fixtures that identify which of the elevators is about to arrive, and depending on which of the lantern fixtures is lit, the direction in which the elevator is currently traveling. The highest and lowest floors have only one lantern fixture in a set of lantern fixtures; the remaining floors have two lanterns per set.
Finally, on major floors such as lobby floors, car position indicator fixtures are provided for each elevator in the group, and report the current floor position of the corresponding elevator car. These are generally not provided on each floor because of the expense. The floor position is taken to be equivalent to the committable floor of the car (that is, the next floor where the car could possibly stop, or a floor where it is stopped). Each of these fixtures requires a pair of wires through the hoistway to carry signals to the fixture from the elevator dispatch controller and a pair of wires through the hoistway to carry electrical power to each of the fixtures. This is true whether a single elevator or a group of elevators is used in the installation.
Regardless of how many individual processors are utilized, multi-elevator groups all employ a car controller for each car, and a group controller for the entire group. Each car controller communicates with the corresponding elevator car by means of a traveling cable, and the various car controllers communicate with the group controller over wires. In turn, the group controller communicates over wires with the hall fixtures.
In large systems, that is, several groups each having 15-25 floors, the amount of wire involved in enormous. Whenever upgrading is to be achieved, modifications to the elevator wiring which is embedded in the building can be extremely difficult, if not sufficiently prohibitive so as to confine the nature of the upgrade to that which will conform to the wiring. When upgrades or new elevator systems are to be provided in occupied buildings, the time required to rewire or reconfigure the wiring of a building can be prohibitive, due to the need to have minimal intrusive shutdown of elevators during the work, so that use of portions of the elevator system by paying tenants can continue throughout the work period.
One approach is to use an electromagnetic transceiver to communicate with one or more corresponding transceivers at a floor which are linked to a hall fixture at that floor. One example of this approach is set forth in International Patent Corporation Treaty Application Number WO 00/34169 entitled xe2x80x9cWireless Elevator Hall Fixturesxe2x80x9d by Finn et al. which is assigned to the assignee of the present invention.
In Finn, the transceivers send call requests and receive acknowledgments for the hall fixtures and send simple on and off signals to the lights associated with the fixtures. Finn mentions using liquid crystal displays in place of the lights. Finn does eliminate the need for wiring between the controllers and the individual floors, and reduces the wiring necessary on each individual floor for this purpose to a minuscule amount. Finn permits altering fixtures without regard to signal wiring already embedded in the building. Finn does eliminate the need for tremendous amounts of wire and provides flexibility. And, the teaching of Finn may be utilized in new construction to save wire and costs and permit future upgrades, as well as being advantageously used in retrofit and upgrade applications to existing systems. However, Finn does not eliminate the need for wiring to carry power to each of the fixtures and to the lights or liquid crystal displays used in place of the lights.
Accordingly, the above art notwithstanding, scientists and engineers working under the direction of applicants assignee have sought to develop ways of avoiding the need to have power wires extend to each of the fixtures.
This invention is in part predicated on the realization that a fixture having an electrophoretic display system is capable of using the electrophoretic display system in connection with wireless communication. It is also in part predicated on the realization that an electrophoretic display system has particular application to elevator systems. This occurs because the wireless communication of information to the electrophoretic display system and the amount of power required to operate the fixture makes possible an independent power source for the fixture. This, in turn, avoids complex and inconvenient wire-like connections to power sources whose remote location makes necessary the complex wiring harnesses discussed above. In particular, this avoids a continuous electrical conductor which extends from the fixture to the hoistway and thence to the power source for the hoistway or for the structure in which the elevator is installed.
An electrophoretic display system 10 is schematically shown in FIG. 1. The electrophoretic display system includes many, many microcompartments, such as microcapsules 12. Each microcapsule contains a liquid 14 and an electrophoretic material 16 disposed in the liquid. Examples of such microcapsules are shown in U.S. Pat. No. 5,961,804 issued to Jacobson et al. entitled xe2x80x9cMicroencapsulated Electrophoretic Display.xe2x80x9d An electrophoretic material is a material that moves in response to an electronic field and includes materials which translate or rotate or both translate or rotate in such a field. As discussed by Jacobson et al., electrophoretic materials for the microcapsules include particles or liquids that are reflective or radiant.
In an electrophoretic display system, the microcapsules are disposed adjacent a device, such as the two electrodes 18, 20 shown in FIG. 1, for imposing an electric field on the electrophoretic material. One example of an electrophoretic display system is the E Ink electronic display which is available from the E Ink Corporation, Cambridge, Mass. A liquid xe2x80x9ccarrier mediumxe2x80x9d is used in one exemplary process to form an xe2x80x9cinkxe2x80x9d that carries and fixes the microcapsules onto virtually any surface. This may be done with existing printing processes, such as, for example, screen printing processes. In one embodiment, the E ink is printed onto a sheet of plastic film that is laminated to a layer of circuitry. The layer of circuitry (electrodes) forms a pattern of pixels that can be controlled by a display driver.
The term xe2x80x9celectrophoretic display systemxe2x80x9d also covers a similar embodiment which is known as the Gyricon system. The Gyricon system uses microscopic, charged balls painted half black and half white. The balls float in tiny liquid filled cavities and rotate in response to an electrical field to form a display. The Gyricon system was developed by the Xerox Corp., Palo Alto Research Center, Palo Alto, Calif.
According to the present invention, an elevator fixture has a wireless communications system which has an electrophoretic display system for receiving and communicating visual information to passengers and which has a source of power connected to the electrophoretic display system that receives energy from the elevator system or its surroundings but is independent of continuous electrical conductors that are attached to a supplementary power source which includes the power system for the hoistway and the power system for the housing in which the elevator is installed.
In accordance with one detailed embodiment of the present invention, the fixture includes a first screen for the electrophoretic display system and a second screen (touchscreen) that lies over the first screen. The second touchscreen has raised symbols on the touchscreen which may be perceived by a person who is visually challenged.
In accordance with one detailed embodiment, the electrophoretic display system has reflective particles and is illuminated by ambient lighting and the power source is a photovoltaic cell which receives energy from the ambient lighting.
In accordance with another detailed embodiment, the power source is a galvanic cell.
In accordance with another detailed embodiment, the power source for the electrophoretic display system has a wireless interface with a supplementary source of power by using electromagnetic energy, for example, with an inductive coupling device for providing energy to a rechargeable galvanic cell.
In accordance with another detailed embodiment, the power source is a galvanic cell which receives energy from a photoelectric cell.
In accordance with another detailed embodiment, the electrophoretic display system has a screen which is curved.
In accordance with another detailed embodiment, at least one of the elevator fixtures is selected from the group consisting of the hall lantern, the hall position indicator, the hall call fixture and the car operating panel display.
A primary feature of the present invention is a fixture for an elevator having an electrophoretic display system. Another feature is the power source for the electrophoretic display system. In one particular embodiment, the power source is a galvanic cell. In one detailed embodiment, the power source is a rechargeable galvanic cell.
A principal advantage of the present invention is the level of safety and reduced maintenance cost and time which results from avoiding the use of the hoistway as a source of power that has wires that are mechanically connected at the hoistway and at the fixture for supplying power to the fixture. Another advantage is the cost of installing fixtures, which results from the ability to locally install the fixture without requiring access to the hoistway. In addition, common hardware for the fixture design may be used for elevators installed in different parts of the world by accommodating different requirements for the language that is displayed by the fixture by electronically adjusting the electric field adjacent the electrophoretic material. Another advantage is the cost of maintenance which results from a less cluttered hoistway by not having wiring associated with supplying power to the fixture extend between the hoistway and the fixture.
The foregoing features and advantages of the present invention will become more apparent in light of the following detailed description of the invention and in the accompanying drawing.